The recent AeroConnect 2016 conference in London included a couple of presentations on satellite antenna technology from Gilat and Phasor.
Yosi Avraham, Business Development Director, Aviation and Mobility, Gilat Satellite Networks, spoke about the difficulties of working with multiple bands, such as both Ka and Ku.
“HTS, on both Ku and Ka, will provide 95% of the future global capacity,” said Avraham. “We see more and more demand for bandwidth from passengers, mainly due to video consumption.
“Many personal electronic devices (PED) can now deliver HD and UHD video content. This is what is driving the demand for bandwidth.
“No one really knows whether Ku or Ka will deliver the bulk of the required bandwidth. In fact, we think it will be split 50:50,” he said.
“Deciding on whether an airline should opt for Ku or Ka is a hard decision that has an impact for many years. One answer is to use both and develop a solution that can offer Ku and Ka-band in one system.
“Now you have flexibility. You can switch between systems while in flight. Also, if you find there are two many users on one satellite you can now switch to another. You also only have to obtain one STC for both systems,” Avraham said.
Dual Ku/Ka antenna
Gilat has an antenna that offers dual Ku/Ka technology. Its ER6000-A antenna was designed to be line-fit with both Boeing and Airbus.
The company says it will offer quick and easy electronic switching between frequency bands and gives reduced network operational costs.
The antenna will be available for certification in early 2017.
ViaSat has gone down a similar route with its Ku/Ka array. It obtained its first STC for its dual-band Ku/Ka-band antenna last year.
The antenna allows an aircraft to use both Ku and Ka-band satellites from one piece of hardware. This works using ViaSat’s “best available service” premise – similar to the way a cell phone roams between 3G, 4G or LTE, but with seamless satellite network-switching.
David Garrood, Chief Satellite Officer, Phasor Inc, said that it was in the final stages of development of an electronically-steerable phased-array antenna.
An electronically-steerable antenna uses beam-forming techniques between multiple elements to electronically move the beam onto the satellite.
The Phasor ESA is just one-inch thick and is conformal so that it can integrate easily with an aircraft fuselage.
Garood said that it is a “software-defined” antenna that can be tailored in real-time to suit its environment, adding the electronically-steered unit is lighter, less complex and more reliable than a conventional mechanically-steered antenna.
“You could arrange to have two beams pointing at two different satellites at once,” he said. “Or put a null into the beam to avoid interference.
“It would also support low-earth orbit satellites with a make-before-break arrangement across two satellites.”
Gogo and Phasor announced last month that they have a research and development partnership for application of the phased-array technology for the in-flight connectivity market.
“The problem with existing solutions is their small apertures,” Garrood said. “As the aperture gets smaller, the beam gets wider, so there is a huge advantage to having a larger antenna. By making a phased-array antenna conformal to the fuselage shape you can make your aperture much larger.
“Big antennas are the only way to get cost-effective bandwidth,” he concluded.